Silent key mechanism for typewriting machines



July 18,1950 J. F. KOCA SILENT KEY MECHANISM FOR TYPEWRITING MACHINES Filed May 1'7, 194'? Patented July 18, 1950 SILENT KEY MECHANISM FOR TYE'EVVRITING MACHINES James F. Koca, Woodstock, Ill., assignor to R. C. Allen Business Machines, 1110., Grand Rapids, Mich, a corporation of Michigan Application May 1'7, 1947, Serial No. 748,719

3 Claims. 1

This invention relates to typewriters in general, and particularly to a key control means for typewriters, More specifically, the invention relates to means associated with a typewriter, to effect or produce. diacritical marks, signs, or symbols for letters, produced by'depressing a typewriter key.

The invention further relates to the provision of new and novel means for rendering the escapement mechanism of a typewriter inoperative upon the depression of a typewriter key, but maintaining the ribbon control and feed operative.

A further object is to provide improved means for causing diacritical marks or other matter, or type on the type bar, to strike the platen for writing or impression purposes, without causing escapement or spacing of the carriage.

More specifically, the invention relates to improved means for raising the ribbon; for effecting escapement or advancement of the carriage during normal operation of the machine, and for preventing escapement of the carriage, but operating to raise the ribbon when operating a key to imprint a diacritical mark, of the type as disclosed in the application of Peter F. Gattuso, Serial No. 560,224, filed October 25, 1944 and since issued as Patent No. 2,459,932 dated January 25, 1949.

Numerous other object and advantages or the invention will be apparent throughout the progress of the following specification.

In the accompanying drawing illustrating the preferred embodiment of the invention, the figure is a detail perspective view of some of the parts of a typewriter, disclosing some of the carriage escapement and ribbon actuating mechanism, the type bar operating mechanism, and also the mechanism for effecting operation of the diacritical mark type bar, independently of the operation of the escapement or carriage advancing mechanism.

The particular construction herein shown for the purpose of illustrating the invention, comprises certain mechanism embodied in the popular, well-known Woodstock typewriter, although the invention is adapted for use with other makes of typewriters and typewriter mechanism.

In the drawing, the mechanism for operating the escapement and ribbon operating mechanism, so far as this invention is concerned, embodies a bar or member 3, which is supported by brackets 4, which are secured to a cross rod or bar 5, journaled in suitable brackets 6, that are secured to a suitable part of the typewriter frame.

Suitable means are provided to maintain the bar or member 3 in normal position, but which permits downward swinging movement thereof upon depression of a key lever I. I

The lever has an operating surface 8, which is adapted to engage alternately spaced long and short teeth or projections 9 and ID, of the bar 3, there being a key lever l for each of the teeth 9 and It. The key lever l is depressed so as to bring the type on the type bar into printing engagement with the paper on the platen, through the ribbon (not shown), in the usual manner.

The escapement mechanism embodies a ratchet wheel H, with which dogs or pawls I2 co-operate, These dogs are mounted upon a pivoted support l3, which is moved in one direction by a spring I 4, Connected to the bar 3, by one end, is an arm or lever I5, that is mounted intermediate its ends, upon the bar or rod 5 for pivotal movement therewith, the other end being pivotally connected, as at It, to a bar or rod l1, that in turn is connected to the support l3, which carries the dogs or pawls I 2.

The bar 3 is moved upon the depression of the key lever 1, to operate the ribbon mechanism and also the escapement mechanism, so as to move the platen one space, conforming to a letter being printed. The bar 3, when depressed by a key lever I, also raises the ribbon (not shown) to bring it into proper alinement with the type bar, and also causes the ribbon to be fed a distance equal to one space, so that the next succeeding key will print through a fresh part of the ribbon.

The invention relates to means for rendering a key dead; that is, for permitting the type controlled by the key lever 1 to be printed, but preventing the carriage from being shifted, and permitting the ribbon to be raised and to be fed in the usual manner. The object of the invention is to a cause a diacritical mark to be printed without shifting the platen and the carriage upon which the platen is supported, so that when a letter to be printed is to be modified by the diacritical mark, the diacritical mark will be in its proper position with respect to the letter which is to be modified or accented, whereby it will not be necessary for the operator to shift the carriage back so as to bring the diacritical mark or other symbol into proper position with respect to the letter to be printed.

The ribbon mechanism, which includes means for raising the ribbon as well as feeding the ribbon, is controlled by the operation of a key lever 1, and also by another key lever l8, for selectively -riage.

anism and a ribbon controlling the printing of a letter, or the printing of a diacritical mark. Therefore, the depression of the lever I will cause the ribbon to be raised and also to be fed, and the escapement of the carriage is actuated. When, however, the diacritical markkey lever I 8 is depressed, the ribbon will be raised, but the escapement mechanism will not be actuated.

The means for controlling the raising and feeding of the ribbon, embodies a bell crank lever l9, which is mounted intermediate its ends, upon the bar or rod 5 for pivotal movement therewith, one end of the lever being secured to the bar 3, as at 20. Carried by the other end 2| of the lever,

is a lug or projection 22, which engages behind an arm or projection 23, on an oscillatory or rock shaft 24, that shifts the ribbon.

When it is desired to print a diacritical mark, the key I8 is depressed, which, as before stated, will actuate the ribbon shifting mechanism, but will not actuate the escapement mechanism. This is accomplished in the following manner:

A second bar is arranged in alinement with the bar 3, and is supported by being attached to one end 26 of a bell crank lever, as at 21. This lever is pivotally mounted intermediate its ends, as at 28, in a bracket or bearing 29. The other end or arm 30 of the lever is provided with a laterally projecting lug or extension 3|, which engages behind an arm or projection 32, secured to and depending from the oscillatory or rock shaft 24.

By the provision of the arms 23 and 32 on the shaft 24, and the levers l9 and 26 with the respective lugs or projections 22 and 3|, it will be manifestthat the shaft 24 may be rocked by the depression of either of the bars 3 or 25, independently with respect to each other. That is, when the bar 3 is depressed by a key 1, the shaft 24 will be rocked a distance sufliciently to raise the ribbon and effect operation of the escapement mechanism, but when a diacritical key i8 is depressed, the shaft 24 will be rocked a distance only suflicient to raise the ribbon, but will not cause the escapement mechanism to be operated.

The bar 25 may also be provided with long and short teeth 33-34, and one key may be provided for each of the teeth. The shaft 24 may be rocked in the opposite direction b any suitable means (not shown) Thus it will be seen that when it is desired to print a diacritical mark, a key 18 controlling that type bar is first depressed, which will cause the ribbon to be shifted and the diacritical mark to be'printed above the space where'the letter to be modified is to be printed, and without actuating the escapement mechanism. Thereafter, the let- -ter key "1 may be actuated, and the letter to be modified will be printed in the proper position with respect to the diacritical mark. The depression of the letter key will also cause the escapement mechanism to be actuated to advance the car- While the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be made in the details of construction, and in the combination and'arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is:

1. In a typewriter having an escapement mechactuating mechanism embodying a ribbon actuating shaft, a depressible bar, a key lever for depressing said bar, means whereby when said bar is depressed said ribbon actuating shaft and said escapement mechanism will be operated, a second depressible bar, independent of and arranged in alinement with the first said bar, an actuating key individual to the last said bar, and means whereby upon depression of the said second bar, said ribbon actuating shaft will be operated independently of the escapement mechanism, and while said escapement mechanism remains inactive.

2. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, a depressible bar, a ke for depressing the bar, an operative connection between the bar and the escapement mechanism, whereby upon depression of said bar, said escapement mechanism will be actuated, an arm on said shaft, a pivotally mounted lever connected to said bar and movable into engagement with said arm upon depression of the bar, to rock said shaft to actuate said ribbon, a second arm on said shaft, a second depressible bar, a pivotally mounted lever connected to said second bar, a portion of said lever adapted to engage the said second arm, to rock the shaft upon depression of the said second bar, whereby to operate the ribbon mechanism independently of the escapement mechanism, and means other than the said key for depressing the said second bar.

3. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, a depressible bar, a key for depressing the bar, an operative connection between the bar and the escapement mechanism, whereby upon depression of said bar, said escapement mechanism will be actuated, an arm on said shaft, a pivotally mounted lever connected to said bar and movable into engagement with said arm upon depression of the bar, to rock said shaft to actuate said ribbon, a second arm on said shaft, 3, second depressible bar, a pivotally mounted lever connected to said second bar, a portion of said lever adapted to engage the said second arm, to rock the shaft upon depression of the said second bar, whereby to operate the ribbon mechanism independently of the escapement mechanism, and means other than the said ke for depressing the said second bar, said second bar being separate from and arranged in alinement with the first said bar, the last said means embodying an actuating key separate from the first said key.

4. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, two separate and distinct depressible bars, arms on said shaft, pivotally mounted levers individual ot the said bars and also to the respective arms, for engaging the arms to rock the shaft upon the selective depression of the bars, and means individual to one of the bars, whereby upon depression thereof the said escapement mechanism will also be actuated.

5. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, two separate and distinct depressible bars, arms on said shaft, means individual to the said bars and also to the respective arms, for engaging the arms to rock the shaft upon the selective depression of the bars, and means individual to one of the bars, whereby upon depression thereof the said escapement mechanism will also be actuated, the

first said means embodying pivotally mounted levers connected to the respective bars, said levers being independent of the respective arms, whereby one of the arms and its respective lever will be moved out of engagement when the other of the levers actuates its respective arm.

6. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, two sep arate and distinct depressible bars, arms on said shaft, means individual to the said bars and also to the respective arms, for engaging the arms to rock the shaft upon the selective depression of the bars, and means individual to one of the bars, whereby upon depression thereof the said escapement mechanism will also be actuated, the first said means embodying bell crank levers, means pivotally mounting said levers intermediate their ends, one end of the levers being connected to the respective bars, the other end of the levers being disposed adjacent the respective said arms and disconnected therefrom, whereby upon selectively depressing one of said bars to rock one of said levers, the other lever and its respective arm will be separated.

7. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, spaced arms connected to said shaft, pivotally mounted bell crank levers individual to said arms and disconnected therefrom, depressible bars individual to said levers, means for selectively depressing the bars, whereby to rock the respective levers to actuate the said shaft, and means also responsive to the depression of only one of said bars, for operating said escapement mechanism.

8. In a typewriter having an escapement mechanism and a ribbon actuating mechanism embodying a ribbon actuating rocker shaft, spaced arms connected to said shaft, pivotally mounted bell crank levers individual to said arms and disconnected therefrom, depressible bars individual to said levers, means for selectively depressing the bars, whereby to rock the respective levers to actuate the said shaft, and means also responsive to the depression of only one of said bars, for operating said escapement mechanism, the said levers and the said arms being so disposed that upon rocking of the said shaft by one of the said levers, the other arm and lever will be separated with respect to each other.

JAMES F. KOCA.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PA'IE'NTS Number Name Date 1,494,716 Seib May 20, 1924 1,546,142 Mamatey July 14, 1925 1,614,297 Handley Jan. 11, 1927 1,741,673 Avery et al Dec. 31, 1929 

